- A connecting band; a fraenum; as, the retinacula of
the ileocaecal and ileocolic valves. - One of the annular ligaments which hold the tendons
close to the bones at the larger joints, as at the wrist and ankle. - One of the retractor muscles of the proboscis of
certain worms. - A small gland or process to which bodies are attached;
as, the glandular retinacula to which the pollinia of orchids are
attached, or the hooks which support the seeds in many acanthaceous
plants.